Bug#30384: Having SQL_BUFFER_RESULT option in the CREATE .. KEY(..) .. SELECT

led to creating corrupted index.

While execution of the  CREATE .. SELECT SQL_BUFFER_RESULT statement the 
engine->start_bulk_insert function was called twice. On the first call
On the first call MyISAM disabled all non-unique indexes and on the second
call it decides to not re-enable them because all indexes was disabled.
Due to this no indexes was actually created during CREATE TABLE thus
producing crashed table.

Now the select_inset class has is_bulk_insert_mode flag which prevents
calling the start_bulk_insert function twice.
The flag is set in the select_create::prepare, select_insert::prepare2
functions and the select_insert class constructor.
The flag is reset in the select_insert::send_eof function.

mysql-test/r/insert_select.result

@@ -830,3 +830,15 @@ id	prev_id	join_id
 3	2	0
 4	3	0
 DROP TABLE t1,t2;
+#
+# Bug#30384: Having SQL_BUFFER_RESULT option in the
+#            CREATE .. KEY(..) .. SELECT led to creating corrupted index.
+#
+create table t1(f1 int);
+insert into t1 values(1),(2),(3);
+create table t2 (key(f1)) engine=myisam select sql_buffer_result f1 from t1;
+check table t2 extended;
+Table	Op	Msg_type	Msg_text
+test.t2	check	status	OK
+drop table t1,t2;
+##################################################################

mysql-test/t/insert_select.test

@@ -385,3 +385,15 @@ INSERT INTO t1 (prev_id) SELECT id
 SELECT * FROM t1;
 
 DROP TABLE t1,t2;
+
+--echo #
+--echo # Bug#30384: Having SQL_BUFFER_RESULT option in the
+--echo #            CREATE .. KEY(..) .. SELECT led to creating corrupted index.
+--echo #
+create table t1(f1 int);
+insert into t1 values(1),(2),(3);
+create table t2 (key(f1)) engine=myisam select sql_buffer_result f1 from t1;
+check table t2 extended;
+drop table t1,t2;
+--echo ##################################################################
+

sql/sql_class.h

@@ -2029,7 +2029,7 @@ class select_insert :public select_result_interceptor {
   ulonglong last_insert_id;
   COPY_INFO info;
   bool insert_into_view;
-
+  bool is_bulk_insert_mode;
   select_insert(TABLE_LIST *table_list_par,
 		TABLE *table_par, List<Item> *fields_par,
 		List<Item> *update_fields, List<Item> *update_values,

sql/sql_insert.cc

@@ -2647,7 +2647,8 @@ select_insert::select_insert(TABLE_LIST *table_list_par, TABLE *table_par,
                              bool ignore_check_option_errors)
   :table_list(table_list_par), table(table_par), fields(fields_par),
    last_insert_id(0),
-   insert_into_view(table_list_par && table_list_par->view != 0)
+   insert_into_view(table_list_par && table_list_par->view != 0),
+   is_bulk_insert_mode(FALSE)
 {
   bzero((char*) &info,sizeof(info));
   info.handle_duplicates= duplic;
@@ -2832,8 +2833,11 @@ int select_insert::prepare2(void)
 {
   DBUG_ENTER("select_insert::prepare2");
   if (thd->lex->current_select->options & OPTION_BUFFER_RESULT &&
-      !thd->prelocked_mode)
+      !thd->prelocked_mode && !is_bulk_insert_mode)
+  {
     table->file->start_bulk_insert((ha_rows) 0);
+    is_bulk_insert_mode= TRUE;
+  }
   DBUG_RETURN(0);
 }
 
@@ -2939,6 +2943,7 @@ bool select_insert::send_eof()
   DBUG_ENTER("select_insert::send_eof");
 
   error= (!thd->prelocked_mode) ? table->file->end_bulk_insert():0;
+  is_bulk_insert_mode= FALSE;
   table->file->extra(HA_EXTRA_NO_IGNORE_DUP_KEY);
   table->file->extra(HA_EXTRA_WRITE_CANNOT_REPLACE);
 
@@ -3271,7 +3276,10 @@ select_create::prepare(List<Item> &values, SELECT_LEX_UNIT *u)
   if (info.handle_duplicates == DUP_UPDATE)
     table->file->extra(HA_EXTRA_INSERT_WITH_UPDATE);
   if (!thd->prelocked_mode)
+  {
     table->file->start_bulk_insert((ha_rows) 0);
+    is_bulk_insert_mode= TRUE;
+  }
   thd->abort_on_warning= (!info.ignore &&
                           (thd->variables.sql_mode &
                            (MODE_STRICT_TRANS_TABLES |